Anxiety Disorders — Causes, Symptoms, Diagnosis & Treatment Guide — Symptoms, Causes & Treatment | MyMedicPlus

Anxiety disorders are a group of psychiatric conditions characterised by excessive, persistent fear and anxiety that is disproportionate to the perceived threat and significantly impairs daily functioning. They are distinct from normal anxiety (a healthy adaptive response to real threats) in their chronicity, intensity, and the degree to which they interfere with everyday life. The principal anxiety disorders (DSM-5/ICD-11) include: generalised anxiety disorder (GAD — excessive worry about multiple domains for more than 6 months), panic disorder (recurrent unexpected panic attacks with anticipatory anxiety), social anxiety disorder (SAD — fear of scrutiny or embarrassment in social situations), specific phobias (intense fear of specific objects or situations), agoraphobia (fear of situations where escape would be difficult), and separation anxiety disorder. Related conditions — post-traumatic stress disorder (PTSD), obsessive-compulsive disorder (OCD), and health anxiety (illness anxiety disorder) — share overlapping mechanisms. Anxiety disorders are highly treatable with psychological therapies and/or pharmacotherapy.

Anxiety disorders result from a complex interaction of biological, psychological, and social factors. Biological: amygdala hyperactivity (the brain's fear centre — in anxiety disorders, the amygdala is overactivated by non-threatening stimuli); dysregulation of the serotonin, noradrenaline, GABA, and glutamate neurotransmitter systems; HPA axis hyperactivation (elevated cortisol); genetic predisposition (heritability 30-60%); temperamental trait of behavioural inhibition in childhood predicts later anxiety. Psychological: cognitive distortions (catastrophising, overestimation of threat, intolerance of uncertainty); avoidance behaviours (maintain and strengthen anxiety through negative reinforcement); childhood adversity (abuse, neglect, parental anxiety, bullying); learned fear responses; perfectionism. Environmental: adverse life events (trauma, bereavement, relationship breakdown, financial stress); work-related stress; social isolation; urban living; social media exposure. Medical mimics: hyperthyroidism (mimics panic disorder), phaeochromocytoma, cardiac arrhythmias (palpitations with anxiety), stimulant use (caffeine, cocaine, amphetamines), alcohol/benzodiazepine withdrawal, and COPD (breathlessness triggers panic).

Psychological symptoms: excessive worry or fear, restlessness or feeling on edge, difficulty concentrating ('mind going blank'), irritability, sense of impending doom, depersonalisation (feeling detached from oneself — common in panic attacks). Physical symptoms (autonomic arousal): palpitations, shortness of breath or hyperventilation, chest tightness, sweating, trembling or shaking, dizziness or lightheadedness, nausea, dry mouth, muscle tension, and headache. Specific disorder presentations: GAD — persistent, uncontrollable worry about multiple everyday concerns (work, health, family, finances) with fatigue, muscle tension, and sleep disturbance. Panic disorder — sudden-onset panic attacks (intense fear peaking within 10 minutes; minimum 4 from: palpitations, sweating, trembling, shortness of breath, choking, chest pain, nausea, dizziness, derealisation, fear of losing control, fear of dying, paraesthesiae, chills/hot flushes); anticipatory anxiety about future attacks; behavioural changes to avoid panic triggers. Social anxiety — intense, persistent fear of social or performance situations; avoidance of social interactions and public speaking; social isolation and impaired occupational functioning. Specific phobia — intense, excessive fear of specific stimuli (heights, spiders, blood, flying, enclosed spaces) triggering immediate anxiety.

Diagnosis is clinical — based on a structured mental health assessment against DSM-5 or ICD-11 diagnostic criteria (symptom type, duration, severity, and functional impairment). Validated screening tools: GAD-7 (7-item; score 0-21; 10 or above suggests moderate anxiety); PHQ-4 (ultra-brief combined anxiety and depression screen); Social Phobia Inventory (SPIN) for social anxiety. Physical examination and blood tests to exclude organic causes: thyroid function tests (TSH, free T4 — hyperthyroidism/hypothyroidism), FBC (anaemia causing breathlessness), blood glucose (hypoglycaemia causing palpitations), ECG (arrhythmias), and 24-hour urine catecholamines for suspected phaeochromocytoma (rare). NICE recommends the stepped care model: Step 1 — GP recognition and psychoeducation; Step 2 — low-intensity interventions (self-help, CBT guided self-help, computerised CBT); Step 3 — high-intensity CBT, medication; Step 4 — specialist mental health assessment. Screen carefully for comorbid depression (affects 60-70% of anxiety disorder patients), substance use, and personality disorders.

Psychological therapies: cognitive behavioural therapy (CBT) — the most extensively evidenced psychological treatment for all anxiety disorders; addresses distorted thoughts (cognitive restructuring) and avoidance behaviours (behavioural experiments and graduated exposure). Exposure and response prevention (ERP — a form of CBT) is essential for phobias (graduated exposure to feared stimuli), OCD, and PTSD. Eye movement desensitisation and reprocessing (EMDR): evidence-based for PTSD. Acceptance and Commitment Therapy (ACT) and mindfulness-based cognitive therapy (MBCT) — emerging strong evidence. Low-intensity interventions: CBT-based guided self-help, computerised CBT (programmes such as SilverCloud, Beating the Blues), and psychoeducation groups. Pharmacotherapy: SSRIs (sertraline, escitalopram, paroxetine, fluoxetine — first-line for GAD, panic disorder, social anxiety, and PTSD; full response takes 4-8 weeks; continue for minimum 12 months after remission). SNRIs (venlafaxine, duloxetine — alternatives to SSRIs for GAD). Pregabalin (licensed for GAD in UK — effective within days; risk of dependence and abuse potential — limited to specialist supervision for prolonged use). Buspirone (partial 5-HT1A agonist — effective for GAD; no dependence risk; requires 2-4 weeks for effect). Avoid long-term benzodiazepines (diazepam, lorazepam) — cause physiological dependence within weeks, cognitive impairment, and paradoxical anxiety on withdrawal; maximum 2-4 weeks. Beta-blockers (propranolol): useful for situational performance anxiety — reduce peripheral somatic symptoms (palpitations, tremor) but not psychological anxiety.

Untreated anxiety disorders generate substantial complications across physical health, occupational functioning, and interpersonal relationships. Functional impairment — reduced work productivity, absenteeism, and inability to maintain employment — is documented in 30-50% of individuals with generalised anxiety disorder (GAD) and panic disorder; the WHO ranks anxiety disorders among the top 10 conditions causing disability-adjusted life years (DALYs). Social isolation and avoidance behaviour progressively restrict an individual's life — agoraphobia developing from panic disorder can confine individuals to their homes, preventing all social and occupational function. Physical health consequences include elevated cortisol from chronic HPA axis activation causing hypertension, cardiovascular disease, immune suppression, gastrointestinal disorders (IBS — anxiety is a major trigger), insomnia, and chronic pain amplification. Comorbid major depressive disorder develops in approximately 60% of individuals with anxiety disorders — significantly worsening prognosis and treatment response. Substance misuse — particularly alcohol and benzodiazepines used for self-medication — occurs in 20-30% of anxiety disorder patients, creating dependency complications. Suicidal ideation is elevated in social anxiety disorder with comorbid depression — 10% of individuals with anxiety disorders report lifetime suicidal ideation. Untreated PTSD after trauma is associated with chronic pain, cardiovascular disease, autoimmune disorders, and premature mortality. Cognitive impairment from chronic anxiety and sleep disturbance affects concentration, memory, and decision-making.

Structured physical exercise (150 minutes of moderate aerobic activity weekly) has robust evidence as an anxiolytic — reduces cortisol, increases GABA, serotonin, and endocannabinoid tone, with effect sizes comparable to medication in mild-moderate anxiety. Mindfulness meditation (MBSR — Mindfulness-Based Stress Reduction programmes): reduces anxiety by training present-moment awareness and reducing rumination. Adequate sleep (7-9 hours nightly — sleep deprivation exacerbates anxiety and impairs emotional regulation). Reduce caffeine consumption (blocks adenosine receptors and increases adrenaline — directly worsens anxiety and panic); limit alcohol (despite short-term anxiolysis, alcohol worsens anxiety on withdrawal and disrupts sleep). Structured problem-solving and time management for GAD-related worry. Social connection — loneliness is a major anxiety risk factor; maintain regular social engagement. Diaphragmatic slow breathing (activates the parasympathetic nervous system, reduces physiological arousal — 4-7-8 breathing technique or box breathing). Use free NHS resources: Every Mind Matters app, IAPT self-referral for CBT access.

Consult your GP if anxiety is persistent (more than 2-4 weeks), is affecting your ability to work, study, or maintain relationships, or is causing significant distress. The GAD-7 questionnaire (available free online) can help quantify whether symptoms warrant professional assessment. Seek urgent help from a mental health crisis team, GP, or A&E for: severe panic attacks causing fear of dying or loss of control, anxiety accompanied by thoughts of self-harm or suicide, or anxiety so severe that it prevents leaving the home or functioning in daily life. If already receiving treatment and symptoms are worsening, contact your treating clinician or the NHS mental health crisis line (111 option 2). Do not stop antidepressants (SSRIs/SNRIs) abruptly without medical advice — gradual dose reduction over weeks to months is required to prevent discontinuation syndrome.